Slowly making my way through all parts/assembly's on my newly purchased LT250R...took apart my FMF silencer. Must have been shot for YEARS, the inside was completely cooked and crispy/hard/flaky:



The inner tube was clogged, a wire brush only worked if I smashed it directly down into the holes but I eventually got it all clean:



I was in a pinch to use what I had laying around so with some research fine steel wool and fiberglass insulation seemed like the best DIY materials I had on hand. I unraveled "finishing" steel wool pads into strips and wound them tightly around the inner tube then tied it down with pieces of welding wire instead of masking tape or tip ties:



I then used home fiberglass insulation, tightly wrapped of course. More welding wire securing the outer fiberglass layer as well (instead of holding both materials with one layer of wire ties on the outside of the insulation):



Almost done, sealed both sides with some Permatex "black" maximum oil resistance gasket maker. The layers might not be 100% evenly dense on all sides but this seems pretty damn good for what I had laying around, I tested it too and it DEFF made a difference; it has a nice deep sound to it now (just don't stand behind the exhaust for a few runs as to not breath in fiberglass):

you neighbors will thank you

That baked on carbon would come right off if you first heat it until it glows with a plumbers torch.  With a silencer that crusted, you also need to heat up and scrape out the carbon in the head pipe area. Nice work on the silencer.  What is the benefit of the steel wool?  I've been using household insulation for decades and it works fine.  Does the steel wool help the fiberglass last longer?

I wouldn't recommend using steel wool in a two-stroke silencer. Oil plus heat plus very​ flammable steel wool isn't a good combination.

I was told a lot of 2-stroke racers fill their entire silencer with steel wool so I figured this would help increase the life span of the fiberglass, it has a nice sound to it but I never thought about the steel wool being flammable. I'm not sure how I would clean the expansion chamber but I can see a spot with oil that bleeds through the metal possibly a rusted out weld point.

stainless steel scour pads from the dollar store, last a long time but doesn't silence very good,  Steelwool will rust fairly fast.  Best stuff I have used is the stringy silent sport stuff.

highmarker, on 03 June 2012 - 03:37 PM, said:

I made sure to use super fine steel wool, and if I have water in my silencer then I have a different problem. Oil covered steel does not rust lol

Here...have a hear for yourself! http://youtu.be/60Ciq0TwMWc?hd=1

Edited by PinkFloydEffect, 05 June 2012 - 12:24 PM.

PinkFloydEffect, on 05 June 2012 - 12:23 PM, said:

Wanna bet?

Chokey is correct.
Not only that, only HIGH grade stainless wool will work in ANY of them.  Otherwise within a few hours, tiny pieces of glowing wires blow out of your silencer, esp in a hot exhaust like a 4T...  Been there, done that.
I am a fiberglass fan myself, quieter than any stainless I have tried, dirt cheap, and easy to use.  Lasts *almost* as long as stainless.  SIlent sport/quality fiberglass is the bomb, but have had swell luck with home insulation as well.  I think Rick Sieman says you cold-climate guys can use home furnace filters, but I have not tried them...

Hmm, I will ride it out for a while and then repack, post my results. What's the worst that can happen the fiberglass catches on fire and burns out? Now I think of it.....that could tourch up the rest of my quad too seeing how throwing sand at an oil fire probably wont help.

PinkFloydEffect, on 06 June 2012 - 12:15 PM, said:

The worst that can happen? Glowing hot little ribbons of steel wool start shooting out the tail pipe and burn the forrest down...

Chokey, on 06 June 2012 - 04:23 PM, said:

  Fires are good. Look at the one that's been burning up half of New Mexico. JK  lol

Quad tards. Can't kill them, but we can hope they kill them selfs.

barcode, on 06 June 2012 - 07:55 PM, said:

woow

txkawboy, on 05 June 2012 - 02:07 PM, said:

The cold climate part is new, but I've read where he said about using furnace filters and they can even be old. Unfortunately, the ones on the market currently, they're kind of thin. Now the one at my old house with the 1980 furnace that made all sorts of bad noises but kept chugging along provided the pilot light stayed lit, that had this super thick filter that would have been ideal.
But I also never saw another one like it, so I just rinsed it out, let it dry and re-installed it.
Pretty sure the new owner replaced it cause the pilot light blew out and the sly HVAC tech that he called insisted it needed to be replaced, being late September/early October when business was slow, he gave the new owner a real sweet deal... which I heard about cause he threatened to sue me for not telling him the furnace was shot.
I told him to take me to court, just be sure to bring the furnace with him, and I'll show the court that the HVAC tech ripped him off.
I did tell him (well, my idiot Realtor who probably didn't tell the new owner which is why he was scammed and pissed at me) that the furnace was noisy but always worked great and if he ever needed it, just call me and I'll show him how to light the pilot light.